Instant‐quality fluorescence in‐situ hybridization as a new tool for HER2 testing in breast cancer: a comparative study. Issue 2 (1st October 2013)

• Record Type: Journal Article
• Authors: Franchet, Camille; Filleron, Thomas; Cayre, Anne; Mounié, Eveline; Penault‐Llorca, Frédérique; Jacquemier, Jocelyne; MacGrogan, Gaëtan; Arnould, Laurent; Lacroix‐Triki, Magali
• Is Part Of: Histopathology. Volume 64:Issue 2(2014)
• Page Start: 274
• Page End: 283
• Publication Date: 2013-10-01
• Subjects: Histology, Pathological -- Periodicals; 611.018
• DOI: 10.1111/his.12247
• Languages: English
• ISSNs: 0309-0167

Abstract

<abstract abstract-type="main" id="his12247-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="his12247-sec-0001" sec-type="section"> <title>Aims</title> <p> <italic>HER2</italic> instant‐quality fluorescence <italic>in‐situ</italic> hybridization (IQFISH) is a new fluorescence <italic>in‐situ</italic> hybridization (FISH) assay developed with a non‐toxic buffer that reduces the hybridization time to 1–2 h, enabling a turnaround time of 3 h 30 min from dewax to counting. The aim of this study was to compare assessment of <italic>HER2</italic> status using IQFISH and assessment using standard FISH.</p> </sec> <sec id="his12247-sec-0002" sec-type="section"> <title>Methods and results</title> <p>We selected 160 breast cancer samples according to their HER2 status as determined by immunohistochemistry (IHC) in a retrospective multicentre cohort (40 cases in each scoring category, i.e. 0/1+/2+/3+). Each participating site (<italic>n</italic> = 5) constructed its tissue microarray (TMA) of 32 archival cases and sent it to the central site (site 1). HER2 IHC, <italic> HER2 </italic>FISH and <italic>HER2 </italic>IQFISH were performed blindly at site 1. IQFISH provided excellent quality signals without any background staining, thus allowing excellent reading conditions even on TMA. Statistical analysis showed almost perfect agreement between IQFISH and FISH (99.3%, <italic>κ</italic> = 0.98). The only discordant case was an equivocal one with an <italic>HER2</italic>/<italic>CEP17</italic> ratio near the ASCO/CAP cut‐off.</p> </sec> <sec id="his12247-sec-0003" sec-type="section"> <title>Conclusions</title> <p>The highly concordant data support IQFISH as a useful alternative to FISH, allowing reliable assessment of <italic>HER2</italic> status. Use of this method could lead to reporting of <italic>HER</italic> status to the oncologist within a day.</p> </sec> </abstract>